"Everything should have a monkey in it," said director Ruben Ostlund.

There are numerous laugh-out-loud moments in The Square, Ruben Ostlund's satirical Cannes competition title that has its world premiere Saturday. But one of the film's more peculiar scenes involves a monkey that randomly appears — without any form of introduction and discussion — in Elizabeth Moss' character's apartment.

"Anything can happen in a movie when suddenly a monkey appears in an apartment," said Ostlund, who last came to Cannes two years ago with Force Majeure. "I love monkeys. And I think that human beings love looking at monkeys, because we are reflecting ourselves in looking at them. Everything should have a monkey in it."

Moss revealed that she received an email from Ostlund that basically said, "so I'm thinking we'll have a monkey."

The actual monkey used was a Bonobo species of monkey called Tiboo — a "very peaceful and friendly monkey," according to Ostland — that the filmmakers shot with for one day in Berlin.

But shooting with the creature came with a strict set of instructions, claimed Claes Bang, who plays the lead character.

"You can't look the monkey in the eye, you can't sing, you can't do anything around it because it might get really aggressive and kill you," he said.

Ostlund later admitted that, in the editing process, he got a note from his producer Philippe Bober about the monkey scenes. "He said, 'I think the monkey is overacting'."